Exhaust machine



March 30, 1954 w. s. SNYDER EXHAUST MACHINE 3 Sheets-Sheet 1 Filed Jan.23, 1947 INVENTOR- l i lliamifinyder fiMw/ k Hls Attorney March 30, 1954w. s. SNYDER EXHAUST MACHINE 3 Sheets-Sheet 2 Filed Jan. 23. 1947 R m WW.

mllidrn zsdsngdel' BY Y I 111's flttarmgy March 30, 1954 w. s. SNYDER2,673,784

EXHAUST MACHINE Filed Jan. 23. 1947 a Sheets-Sheet :s

IN V EN TOR. hi ll iam S. Snyder fi/W WM His Attorney Patented Mar. 30,1954 PATENT OFFICE;

2,673,784 EXHAUST William S. Snyder, Emporium, Pa., assignor to SylvaniaElectric Products, :Inc; a; corporation Me sen er? ApplicationJanuaryfl,194 7 ,rs rialNo, 723.786

This invention relates toexhaust achines for eleotron discharge devicesand the, likef'and' to the electron bombardment and the getterin of vsuch devices, customarily effected during" their evacuation and prior totheir tipping-off. The

invention relates to the machine, and (is, not necessarily. restrictedto. electron discharge ode-Y vices as such, but; extends also to otherdevices 2 which may be ,enclosedin evacuated vessels, such as v relaysand thermaLswitches, which may be in e vacuum orffin a. vesselinitially, evacuated and, later charged with a special gas.

Vacuum tubes, ga eous tubes,v and other devices, which have metal partsenclosed in a vessel or envelope that is evacuated. at some part of themanufacturing process commonly have a gettering tabarranged.criticallyin relation to e q ma n er 'r h ecta art hose metalarts ca'n. be. inductively" heated by, radio frequency,.current lto havelion .7 the I gases fincluded within oron thensurface gthemetahand,after final evacuatio n' of gases, thergjettering tab may independentlybe, inductively, heated for flashing, Asis well known the. flashingvaporiz'es the gettering vmetal whichfledsorbsg ininutequantities;-t,;ga s remaining. object ,of the ,presr-f ent 7 inventionis to. rovide; new, and, effective. omba nt fi ,P '-fl j i e; vic s qlixr r heist mach e In, one line of tiny radio, tubes, including icontrolled; as typesftheg ette ns eb is l o' l dr i b t h J c-J tionof,the Y vexhaust tribulation. with the remain-V fi um. type nd gri den ofthe envelope, and atan. an l tothe' come mon axis o f the exhausttubulation and the en-d velope. It is afurther-vobjectfof.thisrinvention otnrovid tro m ard e t p s irk a mgthe, metal-- parts; er? 'siichif'dey'i esfwithoutr fiashi g; the getter,and ,for'indpendently.flash-r ing the getter withoutundulyheatingthemetal parts. A, further object is, to improve, the.construction of induction-heating coils for getter-t flashing and ,likepurposes.

The embodiment of L the invention for accon plishing'theseobjectsincludesa carrier for movingthe unevacuated vessels or. envelopes, con-, tainingthe metal parts andthe gett erin'g tab, successively pastthe bombardmentcoil and the getter flashingcoil which areusualintexhaustmachines. In the present machine thebombardk mentcoils, arelocated-adjacent the pathof the vessQl; While thegettergflashing coilis. recipe oceble; n o an out l f he at f h v ssel it is carried throughthe exhaust cycle," The} et erlash n ilshqu dl deve op afield iii-"metals-i ter! 6 Cl ims-o mean) 2 tense enough to flash. the getter,while at the sanieijtime it should be directed so that nofin ten epartof it willundulylreh'eat the previously bombardeclmetal' partsenclosedin the vessel? Tothi'sf end the getter-flashing coilisso shapedf asfto' partly embrace the vessel and allow rel ative reciprocationparallel'to the envelope which'f is in getter-flashing position,portiqfisof each- "Fig. 1 is a fragmentary plan viewer an exhaustmachine embodying thelpresent invention; showing one of a series 01bombardmentstaf tions and the getter-flashing station;

Fig. zflis an elvationrpartly sectio bombardment station getter flashingstation;

Fig 4vis anen1arged view, partly in section, of the gette'nflashihg coilin relation to the 'et- -Fig. 3 is an elevation, partly in section, ofthe ter, the enclosing vessel being "partly broken" away to show thegetterjing tab;

Fig, 5 is an ehIarged'partIy sectional view of thelbombardment coil initsfrelationjship to an" electron discharge devicelfthe internalelements'j of which are disclosed by a broken-awayi section;

of its'fenvelopeg Fla, 6 is an end view of the coils in Fig. 5; and

Figs. 7 andfl are aplan' viewfand a lateral ele f vation'respectively,of 'the getter fiashing coil'fin" EfigsQl,'3 ,and'4.

Referring now to the drawings, there will be describeda preferredarrangeinent for pemba q:

mggthe 'metal, electrodes (Fig; supported within, g'lassflve ssel vonjleadsL'which are sealed throughthe glass. An exhaust tubulation If isattached to vessel V, by means of which the vessel is supported whilebeing exhausted,

- bombarded, while, the getter is being flashed, and

until. the time that, the junctiorr of tribulation Tfand vessel V isheatsoftenedftoseal on the vessel. Exhaust tubulationT also serves asthe connectionbetween vessel V and the exhaust system in thejmachine forevacuating the vessel before, and during the bombardment, and to simply.anyfnecessa'ry gas to; the vessel. As shown in Figs. 4 and 5,'a getterelement G is supported on the ssernblyjo i electrodesE and is ,cti n bi;Y SQIV h 3211- 3 lation T and at an angle to the common axis of thevessel and the tubulation.

Each tubulation T is supported vertically on a bracket I2 carried byturret l0, being gripped within the end M of a line (not shown) throughbracket I2 to an exhaust pump. The turret is intermittently indexed tocarry the vessels being evacuated in a horizontal circular pathsuccessively past a series of exhaust stations, the last of which isshown at A in Fig. l, and then past getter-flashing station B andultimately to a tipping-off station where the junction of vessel V withexhaust tubulation T is fused and the vessel is removed from themachine. In the present instance the long dimension of the electrodes isalong the axis of the vessel.

A two-part bombarder coil l6 of metal tubing is supported adjustably atstation A with its axis at right angles to the path of vessels V and totheir axes. With the coil axis arranged thus radially of the turret, itis possible to develop a uniform high-frequency field for heatingelectrodes T and thus driving off the occluded and the surface gases.This induction heater is best shown in Fig. wherein the two parts of thecoil are shown joined by metal coupling 18. Multiple cords 20 of glassfiber hold the several turns of each layer of turns close to each otherbut insulated apart, and a flexible sheet 22 of insulation separates thelayer of the coil. A high frequency generator (not shown) energizes thecoils which are conventionally cooled by circulating liquid within thetubing. Coil i6 is carried adjustably by insulating block 24 clamped torod 26 upstanding from segmental rim 28, carried in turn on rod 39projecting from stationary bracket 32 on the machine base. The axis ofcoil Iii is at a level midway along the length of electrode assembly E,and is radial of carrier Ill.

At station B the getter-flashing coil 34 is shown. This coil issimilarly of metal tubing for circulation of cooling fluid and is alsoenergized from a high frequency source (not shown). When coil 34 is inposition for flashing the get ter (Fig. 4) itis in the path of vessel V,but the turret is stationary at this time. Coil 34 is sup ported oninsulating block 36 carried by rod 38 on segmental support 40. Unlikesupport 28,

segmental support 40 is vertically movable, bet ing carried by slide 42in stationary guide 44 on the mach ne base. At the lower end of slide42. cam follower 46 is in engagement with cam 48 on shaft 59 whichrotates once for each operation of the turret indexing mechanism (notshown), so as to lower the coil after carrier [0 comes to rest and raiseit before renewed in-'- dexing has commenced.

From Figs. 4, '7 and 8 it will be evident that coil 34 is free toreciprocate vertically while embracing vessel V, and that the upper halfof each turn of the coil lies in a plane parallel to generally flatgetter element G. The lower portions of the respective turns are bentout of the plane of the aforementioned parts of the several turns, inorder that the coil may be raised freely. Were the entire coil merelymade of oblique helical turns the field would be either too weak toflash the getter, or if strong enough, would harmfully reheat theelectrodes E. The bent-away portions of each of the turns produces afield more or less transverse to exhaust it isneither wasteful nordamaging.

Just as in the case of bombardment coil I6,

, said envelopes.

coil 34 is made in two layers separated by a. sheet of insulation 22,and the several turns of the coil are held together but separated bycords 28 of glass fiber.

The sequence of operations in this machine follows that in other wellknown exhaust machines, in that a series of bombardment stations isfollowed by a getter-flashing station. The orientation of thebombardment coils and the getter-flashing coil is such that the actionof each is relatively independent of the other. However, the particularconfiguration of the getter-flashing coil which promotes emcientflashing, in relation to the small vessel described, requires a specialpositioning of the bombardment coils if reheating of the electrodes isto be avoided. It will be recognized that the various parts are subjectto modifications by those skilled in the art, and that the novelconstruction may be used for other purposes. Therefore itshould beunderstood that the specific disclosure is intended to be illustrativeand not as a limitation.

and getter-flashing positions, an induction heating coil locatedlaterally of the path of the envelopes for inductively heating thecontents thereof, a getter-flashing coil mounted for movement into thepath of the envelopes, said last mentioned coil being so warped so as toclosely embrace a portion of each of the envelopes in succession, andmeans for alternately moving the coil into said path and removing it intimed relation with the movement of said carrier.

2. The combination according to claim 1 where'n said getter-flashingcoil includes a plurality of turns most of each of which lies inrespective parallel planes intersecting that envelope which is in getter-fiashing position, the remainder of each of the turns being bent awayfrom said planes and from the envelope.

3. The combination, in an exhaust machine 3 for electron tubes having anenclosing envelope obliquely, a stationary induction heating coiladjacent the path of the envelope having an axis transverse to the pathand axis of the envelope,

and a getter-flashing coil reciprocable into and F out of the path ofthe envelope having turns only part of each of which lies in a planeparallel to the gettering element when the envelope is ingetter-flashing position whereby substantially only said getter elementis heated by said getter flashing coil.

4. In an envelope exhausting machine, a car rier for moving saidenvelope successively past an induction heating station and a getterflashing station, induction coils at each of said stations, the coil atthe first mentioned station being located laterally of the path of saidenvelopes for heating conductive material within said envelopes, thecoil at the second of said stations being laterally movable into and outof the path of said envelopes in timed relation with the movement ofsaid carrier, and said last mentioned coil being so curved as to partlyembrace a portion of each envelope '5, In an envelope exhaustingmachine, a carwhen in the path oirier for moving said envelopesuccessively past an induction heating station and a getter flashingstation, induction coils at each of said stations, the coil at the firstmentioned station being located laterally of the path of said envelopesfor heating conductive material within said envelopes, the coil at thesecond of said stations being laterally movable into and out of the pathof said envelopes in timed relation with the movement of said carrier,and said last mentioned coil including a plurality of turns most of eachof which lies in a plane parallel to an element within said envelope,the remainder of each of said turns being bent to lie in planes at anangle to said element whereby only said element is heated to asubstantial extent, and being so curved as to partly embrace a portionof each envelope when in the path of said envelopes.

6. In an envelope exhaust machine, a carrier for moving said envelopesuccessively past an induction heating station and a getter flashingstation, induction coils at each of said stations, the coil at the firstmentioned station being 10-- cated laterally of the path of saidenvelopes for heating conductive material within said envelope. the coilat the second or said stations being laterally movable into and out ofthe path ofsaid envelopes in timed relation with the movement of saidcarrier, and said last mentioned coil having a number 01' turns, an arcof each of which lies in a surface partly embracing said envelope whenin the path of said envelopes, the remainder of each of said turns beingbent to lie in a surface at an angle to the surface of said are and awayfrom the envelope.

7 WILLIAM S. SNYDER.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,758,004 Madden May 13, 1930 1,904,214 Fagan Apr. 18, 19332,006,771 Kayko July 2, 1935 2,452,162 Stanton et a1. Oct. 26, 1948

